An X-ray computed tomography apparatus includes a bed which moves a table top on which a subject is placed. In order to obtain an image with higher fineness, reduction in vibration of the table top at a time of insertion into a bore is required. This being the case, a novel two-stage sliding-type bed has been under development. This bed includes a mechanism which can independently slide a table top and a support frame which supports the table top, and has a configuration that the support frame moves forward to the gantry in interlock with lifting of the table top. By this configuration, the support frame can be moved as close as possible to the gantry with a high throughput, and the reduction of vibration of the table top can be realized. On the other hand, there is a demand for vertical lifting of the table top relative to the floor surface.